https://processing.org/tutorials/arrays/
An array is a container that holds a fixed number of values, a bit like a spreadsheet table. With arrays we can store multiple variables of the same type, and access them easily.
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Arrays can also be imagined as drawers, with variables stored in each drawer. The drawer has a certain type, and each drawer store another set of draws (multidimensional). The individual drawers are numbered and start at 0. The size or the length is stored in the variable 'length'. Arrays are not dynamic, that means they can not change their length at runtime. If you need a dynamic array, you should use ArrayList.
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